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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/usb/host/ehci-sched.c
downloadlinux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.bz2
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'drivers/usb/host/ehci-sched.c')
-rw-r--r--drivers/usb/host/ehci-sched.c1999
1 files changed, 1999 insertions, 0 deletions
diff --git a/drivers/usb/host/ehci-sched.c b/drivers/usb/host/ehci-sched.c
new file mode 100644
index 000000000000..f6c86354e304
--- /dev/null
+++ b/drivers/usb/host/ehci-sched.c
@@ -0,0 +1,1999 @@
+/*
+ * Copyright (c) 2001-2004 by David Brownell
+ * Copyright (c) 2003 Michal Sojka, for high-speed iso transfers
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+/* this file is part of ehci-hcd.c */
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * EHCI scheduled transaction support: interrupt, iso, split iso
+ * These are called "periodic" transactions in the EHCI spec.
+ *
+ * Note that for interrupt transfers, the QH/QTD manipulation is shared
+ * with the "asynchronous" transaction support (control/bulk transfers).
+ * The only real difference is in how interrupt transfers are scheduled.
+ *
+ * For ISO, we make an "iso_stream" head to serve the same role as a QH.
+ * It keeps track of every ITD (or SITD) that's linked, and holds enough
+ * pre-calculated schedule data to make appending to the queue be quick.
+ */
+
+static int ehci_get_frame (struct usb_hcd *hcd);
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * periodic_next_shadow - return "next" pointer on shadow list
+ * @periodic: host pointer to qh/itd/sitd
+ * @tag: hardware tag for type of this record
+ */
+static union ehci_shadow *
+periodic_next_shadow (union ehci_shadow *periodic, __le32 tag)
+{
+ switch (tag) {
+ case Q_TYPE_QH:
+ return &periodic->qh->qh_next;
+ case Q_TYPE_FSTN:
+ return &periodic->fstn->fstn_next;
+ case Q_TYPE_ITD:
+ return &periodic->itd->itd_next;
+ // case Q_TYPE_SITD:
+ default:
+ return &periodic->sitd->sitd_next;
+ }
+}
+
+/* caller must hold ehci->lock */
+static void periodic_unlink (struct ehci_hcd *ehci, unsigned frame, void *ptr)
+{
+ union ehci_shadow *prev_p = &ehci->pshadow [frame];
+ __le32 *hw_p = &ehci->periodic [frame];
+ union ehci_shadow here = *prev_p;
+
+ /* find predecessor of "ptr"; hw and shadow lists are in sync */
+ while (here.ptr && here.ptr != ptr) {
+ prev_p = periodic_next_shadow (prev_p, Q_NEXT_TYPE (*hw_p));
+ hw_p = here.hw_next;
+ here = *prev_p;
+ }
+ /* an interrupt entry (at list end) could have been shared */
+ if (!here.ptr)
+ return;
+
+ /* update shadow and hardware lists ... the old "next" pointers
+ * from ptr may still be in use, the caller updates them.
+ */
+ *prev_p = *periodic_next_shadow (&here, Q_NEXT_TYPE (*hw_p));
+ *hw_p = *here.hw_next;
+}
+
+/* how many of the uframe's 125 usecs are allocated? */
+static unsigned short
+periodic_usecs (struct ehci_hcd *ehci, unsigned frame, unsigned uframe)
+{
+ __le32 *hw_p = &ehci->periodic [frame];
+ union ehci_shadow *q = &ehci->pshadow [frame];
+ unsigned usecs = 0;
+
+ while (q->ptr) {
+ switch (Q_NEXT_TYPE (*hw_p)) {
+ case Q_TYPE_QH:
+ /* is it in the S-mask? */
+ if (q->qh->hw_info2 & cpu_to_le32 (1 << uframe))
+ usecs += q->qh->usecs;
+ /* ... or C-mask? */
+ if (q->qh->hw_info2 & cpu_to_le32 (1 << (8 + uframe)))
+ usecs += q->qh->c_usecs;
+ hw_p = &q->qh->hw_next;
+ q = &q->qh->qh_next;
+ break;
+ // case Q_TYPE_FSTN:
+ default:
+ /* for "save place" FSTNs, count the relevant INTR
+ * bandwidth from the previous frame
+ */
+ if (q->fstn->hw_prev != EHCI_LIST_END) {
+ ehci_dbg (ehci, "ignoring FSTN cost ...\n");
+ }
+ hw_p = &q->fstn->hw_next;
+ q = &q->fstn->fstn_next;
+ break;
+ case Q_TYPE_ITD:
+ usecs += q->itd->usecs [uframe];
+ hw_p = &q->itd->hw_next;
+ q = &q->itd->itd_next;
+ break;
+ case Q_TYPE_SITD:
+ /* is it in the S-mask? (count SPLIT, DATA) */
+ if (q->sitd->hw_uframe & cpu_to_le32 (1 << uframe)) {
+ if (q->sitd->hw_fullspeed_ep &
+ __constant_cpu_to_le32 (1<<31))
+ usecs += q->sitd->stream->usecs;
+ else /* worst case for OUT start-split */
+ usecs += HS_USECS_ISO (188);
+ }
+
+ /* ... C-mask? (count CSPLIT, DATA) */
+ if (q->sitd->hw_uframe &
+ cpu_to_le32 (1 << (8 + uframe))) {
+ /* worst case for IN complete-split */
+ usecs += q->sitd->stream->c_usecs;
+ }
+
+ hw_p = &q->sitd->hw_next;
+ q = &q->sitd->sitd_next;
+ break;
+ }
+ }
+#ifdef DEBUG
+ if (usecs > 100)
+ ehci_err (ehci, "uframe %d sched overrun: %d usecs\n",
+ frame * 8 + uframe, usecs);
+#endif
+ return usecs;
+}
+
+/*-------------------------------------------------------------------------*/
+
+static int same_tt (struct usb_device *dev1, struct usb_device *dev2)
+{
+ if (!dev1->tt || !dev2->tt)
+ return 0;
+ if (dev1->tt != dev2->tt)
+ return 0;
+ if (dev1->tt->multi)
+ return dev1->ttport == dev2->ttport;
+ else
+ return 1;
+}
+
+/* return true iff the device's transaction translator is available
+ * for a periodic transfer starting at the specified frame, using
+ * all the uframes in the mask.
+ */
+static int tt_no_collision (
+ struct ehci_hcd *ehci,
+ unsigned period,
+ struct usb_device *dev,
+ unsigned frame,
+ u32 uf_mask
+)
+{
+ if (period == 0) /* error */
+ return 0;
+
+ /* note bandwidth wastage: split never follows csplit
+ * (different dev or endpoint) until the next uframe.
+ * calling convention doesn't make that distinction.
+ */
+ for (; frame < ehci->periodic_size; frame += period) {
+ union ehci_shadow here;
+ __le32 type;
+
+ here = ehci->pshadow [frame];
+ type = Q_NEXT_TYPE (ehci->periodic [frame]);
+ while (here.ptr) {
+ switch (type) {
+ case Q_TYPE_ITD:
+ type = Q_NEXT_TYPE (here.itd->hw_next);
+ here = here.itd->itd_next;
+ continue;
+ case Q_TYPE_QH:
+ if (same_tt (dev, here.qh->dev)) {
+ u32 mask;
+
+ mask = le32_to_cpu (here.qh->hw_info2);
+ /* "knows" no gap is needed */
+ mask |= mask >> 8;
+ if (mask & uf_mask)
+ break;
+ }
+ type = Q_NEXT_TYPE (here.qh->hw_next);
+ here = here.qh->qh_next;
+ continue;
+ case Q_TYPE_SITD:
+ if (same_tt (dev, here.sitd->urb->dev)) {
+ u16 mask;
+
+ mask = le32_to_cpu (here.sitd
+ ->hw_uframe);
+ /* FIXME assumes no gap for IN! */
+ mask |= mask >> 8;
+ if (mask & uf_mask)
+ break;
+ }
+ type = Q_NEXT_TYPE (here.sitd->hw_next);
+ here = here.sitd->sitd_next;
+ continue;
+ // case Q_TYPE_FSTN:
+ default:
+ ehci_dbg (ehci,
+ "periodic frame %d bogus type %d\n",
+ frame, type);
+ }
+
+ /* collision or error */
+ return 0;
+ }
+ }
+
+ /* no collision */
+ return 1;
+}
+
+/*-------------------------------------------------------------------------*/
+
+static int enable_periodic (struct ehci_hcd *ehci)
+{
+ u32 cmd;
+ int status;
+
+ /* did clearing PSE did take effect yet?
+ * takes effect only at frame boundaries...
+ */
+ status = handshake (&ehci->regs->status, STS_PSS, 0, 9 * 125);
+ if (status != 0) {
+ ehci_to_hcd(ehci)->state = HC_STATE_HALT;
+ return status;
+ }
+
+ cmd = readl (&ehci->regs->command) | CMD_PSE;
+ writel (cmd, &ehci->regs->command);
+ /* posted write ... PSS happens later */
+ ehci_to_hcd(ehci)->state = HC_STATE_RUNNING;
+
+ /* make sure ehci_work scans these */
+ ehci->next_uframe = readl (&ehci->regs->frame_index)
+ % (ehci->periodic_size << 3);
+ return 0;
+}
+
+static int disable_periodic (struct ehci_hcd *ehci)
+{
+ u32 cmd;
+ int status;
+
+ /* did setting PSE not take effect yet?
+ * takes effect only at frame boundaries...
+ */
+ status = handshake (&ehci->regs->status, STS_PSS, STS_PSS, 9 * 125);
+ if (status != 0) {
+ ehci_to_hcd(ehci)->state = HC_STATE_HALT;
+ return status;
+ }
+
+ cmd = readl (&ehci->regs->command) & ~CMD_PSE;
+ writel (cmd, &ehci->regs->command);
+ /* posted write ... */
+
+ ehci->next_uframe = -1;
+ return 0;
+}
+
+/*-------------------------------------------------------------------------*/
+
+/* periodic schedule slots have iso tds (normal or split) first, then a
+ * sparse tree for active interrupt transfers.
+ *
+ * this just links in a qh; caller guarantees uframe masks are set right.
+ * no FSTN support (yet; ehci 0.96+)
+ */
+static int qh_link_periodic (struct ehci_hcd *ehci, struct ehci_qh *qh)
+{
+ unsigned i;
+ unsigned period = qh->period;
+
+ dev_dbg (&qh->dev->dev,
+ "link qh%d-%04x/%p start %d [%d/%d us]\n",
+ period, le32_to_cpup (&qh->hw_info2) & 0xffff,
+ qh, qh->start, qh->usecs, qh->c_usecs);
+
+ /* high bandwidth, or otherwise every microframe */
+ if (period == 0)
+ period = 1;
+
+ for (i = qh->start; i < ehci->periodic_size; i += period) {
+ union ehci_shadow *prev = &ehci->pshadow [i];
+ u32 *hw_p = &ehci->periodic [i];
+ union ehci_shadow here = *prev;
+ u32 type = 0;
+
+ /* skip the iso nodes at list head */
+ while (here.ptr) {
+ type = Q_NEXT_TYPE (*hw_p);
+ if (type == Q_TYPE_QH)
+ break;
+ prev = periodic_next_shadow (prev, type);
+ hw_p = &here.qh->hw_next;
+ here = *prev;
+ }
+
+ /* sorting each branch by period (slow-->fast)
+ * enables sharing interior tree nodes
+ */
+ while (here.ptr && qh != here.qh) {
+ if (qh->period > here.qh->period)
+ break;
+ prev = &here.qh->qh_next;
+ hw_p = &here.qh->hw_next;
+ here = *prev;
+ }
+ /* link in this qh, unless some earlier pass did that */
+ if (qh != here.qh) {
+ qh->qh_next = here;
+ if (here.qh)
+ qh->hw_next = *hw_p;
+ wmb ();
+ prev->qh = qh;
+ *hw_p = QH_NEXT (qh->qh_dma);
+ }
+ }
+ qh->qh_state = QH_STATE_LINKED;
+ qh_get (qh);
+
+ /* update per-qh bandwidth for usbfs */
+ ehci_to_hcd(ehci)->self.bandwidth_allocated += qh->period
+ ? ((qh->usecs + qh->c_usecs) / qh->period)
+ : (qh->usecs * 8);
+
+ /* maybe enable periodic schedule processing */
+ if (!ehci->periodic_sched++)
+ return enable_periodic (ehci);
+
+ return 0;
+}
+
+static void qh_unlink_periodic (struct ehci_hcd *ehci, struct ehci_qh *qh)
+{
+ unsigned i;
+ unsigned period;
+
+ // FIXME:
+ // IF this isn't high speed
+ // and this qh is active in the current uframe
+ // (and overlay token SplitXstate is false?)
+ // THEN
+ // qh->hw_info1 |= __constant_cpu_to_le32 (1 << 7 /* "ignore" */);
+
+ /* high bandwidth, or otherwise part of every microframe */
+ if ((period = qh->period) == 0)
+ period = 1;
+
+ for (i = qh->start; i < ehci->periodic_size; i += period)
+ periodic_unlink (ehci, i, qh);
+
+ /* update per-qh bandwidth for usbfs */
+ ehci_to_hcd(ehci)->self.bandwidth_allocated -= qh->period
+ ? ((qh->usecs + qh->c_usecs) / qh->period)
+ : (qh->usecs * 8);
+
+ dev_dbg (&qh->dev->dev,
+ "unlink qh%d-%04x/%p start %d [%d/%d us]\n",
+ qh->period, le32_to_cpup (&qh->hw_info2) & 0xffff,
+ qh, qh->start, qh->usecs, qh->c_usecs);
+
+ /* qh->qh_next still "live" to HC */
+ qh->qh_state = QH_STATE_UNLINK;
+ qh->qh_next.ptr = NULL;
+ qh_put (qh);
+
+ /* maybe turn off periodic schedule */
+ ehci->periodic_sched--;
+ if (!ehci->periodic_sched)
+ (void) disable_periodic (ehci);
+}
+
+static void intr_deschedule (struct ehci_hcd *ehci, struct ehci_qh *qh)
+{
+ unsigned wait;
+
+ qh_unlink_periodic (ehci, qh);
+
+ /* simple/paranoid: always delay, expecting the HC needs to read
+ * qh->hw_next or finish a writeback after SPLIT/CSPLIT ... and
+ * expect khubd to clean up after any CSPLITs we won't issue.
+ * active high speed queues may need bigger delays...
+ */
+ if (list_empty (&qh->qtd_list)
+ || (__constant_cpu_to_le32 (0x0ff << 8)
+ & qh->hw_info2) != 0)
+ wait = 2;
+ else
+ wait = 55; /* worst case: 3 * 1024 */
+
+ udelay (wait);
+ qh->qh_state = QH_STATE_IDLE;
+ qh->hw_next = EHCI_LIST_END;
+ wmb ();
+}
+
+/*-------------------------------------------------------------------------*/
+
+static int check_period (
+ struct ehci_hcd *ehci,
+ unsigned frame,
+ unsigned uframe,
+ unsigned period,
+ unsigned usecs
+) {
+ int claimed;
+
+ /* complete split running into next frame?
+ * given FSTN support, we could sometimes check...
+ */
+ if (uframe >= 8)
+ return 0;
+
+ /*
+ * 80% periodic == 100 usec/uframe available
+ * convert "usecs we need" to "max already claimed"
+ */
+ usecs = 100 - usecs;
+
+ /* we "know" 2 and 4 uframe intervals were rejected; so
+ * for period 0, check _every_ microframe in the schedule.
+ */
+ if (unlikely (period == 0)) {
+ do {
+ for (uframe = 0; uframe < 7; uframe++) {
+ claimed = periodic_usecs (ehci, frame, uframe);
+ if (claimed > usecs)
+ return 0;
+ }
+ } while ((frame += 1) < ehci->periodic_size);
+
+ /* just check the specified uframe, at that period */
+ } else {
+ do {
+ claimed = periodic_usecs (ehci, frame, uframe);
+ if (claimed > usecs)
+ return 0;
+ } while ((frame += period) < ehci->periodic_size);
+ }
+
+ // success!
+ return 1;
+}
+
+static int check_intr_schedule (
+ struct ehci_hcd *ehci,
+ unsigned frame,
+ unsigned uframe,
+ const struct ehci_qh *qh,
+ __le32 *c_maskp
+)
+{
+ int retval = -ENOSPC;
+ u8 mask;
+
+ if (qh->c_usecs && uframe >= 6) /* FSTN territory? */
+ goto done;
+
+ if (!check_period (ehci, frame, uframe, qh->period, qh->usecs))
+ goto done;
+ if (!qh->c_usecs) {
+ retval = 0;
+ *c_maskp = 0;
+ goto done;
+ }
+
+ /* Make sure this tt's buffer is also available for CSPLITs.
+ * We pessimize a bit; probably the typical full speed case
+ * doesn't need the second CSPLIT.
+ *
+ * NOTE: both SPLIT and CSPLIT could be checked in just
+ * one smart pass...
+ */
+ mask = 0x03 << (uframe + qh->gap_uf);
+ *c_maskp = cpu_to_le32 (mask << 8);
+
+ mask |= 1 << uframe;
+ if (tt_no_collision (ehci, qh->period, qh->dev, frame, mask)) {
+ if (!check_period (ehci, frame, uframe + qh->gap_uf + 1,
+ qh->period, qh->c_usecs))
+ goto done;
+ if (!check_period (ehci, frame, uframe + qh->gap_uf,
+ qh->period, qh->c_usecs))
+ goto done;
+ retval = 0;
+ }
+done:
+ return retval;
+}
+
+/* "first fit" scheduling policy used the first time through,
+ * or when the previous schedule slot can't be re-used.
+ */
+static int qh_schedule (struct ehci_hcd *ehci, struct ehci_qh *qh)
+{
+ int status;
+ unsigned uframe;
+ __le32 c_mask;
+ unsigned frame; /* 0..(qh->period - 1), or NO_FRAME */
+
+ qh_refresh(ehci, qh);
+ qh->hw_next = EHCI_LIST_END;
+ frame = qh->start;
+
+ /* reuse the previous schedule slots, if we can */
+ if (frame < qh->period) {
+ uframe = ffs (le32_to_cpup (&qh->hw_info2) & 0x00ff);
+ status = check_intr_schedule (ehci, frame, --uframe,
+ qh, &c_mask);
+ } else {
+ uframe = 0;
+ c_mask = 0;
+ status = -ENOSPC;
+ }
+
+ /* else scan the schedule to find a group of slots such that all
+ * uframes have enough periodic bandwidth available.
+ */
+ if (status) {
+ /* "normal" case, uframing flexible except with splits */
+ if (qh->period) {
+ frame = qh->period - 1;
+ do {
+ for (uframe = 0; uframe < 8; uframe++) {
+ status = check_intr_schedule (ehci,
+ frame, uframe, qh,
+ &c_mask);
+ if (status == 0)
+ break;
+ }
+ } while (status && frame--);
+
+ /* qh->period == 0 means every uframe */
+ } else {
+ frame = 0;
+ status = check_intr_schedule (ehci, 0, 0, qh, &c_mask);
+ }
+ if (status)
+ goto done;
+ qh->start = frame;
+
+ /* reset S-frame and (maybe) C-frame masks */
+ qh->hw_info2 &= __constant_cpu_to_le32 (~0xffff);
+ qh->hw_info2 |= qh->period
+ ? cpu_to_le32 (1 << uframe)
+ : __constant_cpu_to_le32 (0xff);
+ qh->hw_info2 |= c_mask;
+ } else
+ ehci_dbg (ehci, "reused qh %p schedule\n", qh);
+
+ /* stuff into the periodic schedule */
+ status = qh_link_periodic (ehci, qh);
+done:
+ return status;
+}
+
+static int intr_submit (
+ struct ehci_hcd *ehci,
+ struct usb_host_endpoint *ep,
+ struct urb *urb,
+ struct list_head *qtd_list,
+ int mem_flags
+) {
+ unsigned epnum;
+ unsigned long flags;
+ struct ehci_qh *qh;
+ int status = 0;
+ struct list_head empty;
+
+ /* get endpoint and transfer/schedule data */
+ epnum = ep->desc.bEndpointAddress;
+
+ spin_lock_irqsave (&ehci->lock, flags);
+
+ /* get qh and force any scheduling errors */
+ INIT_LIST_HEAD (&empty);
+ qh = qh_append_tds (ehci, urb, &empty, epnum, &ep->hcpriv);
+ if (qh == NULL) {
+ status = -ENOMEM;
+ goto done;
+ }
+ if (qh->qh_state == QH_STATE_IDLE) {
+ if ((status = qh_schedule (ehci, qh)) != 0)
+ goto done;
+ }
+
+ /* then queue the urb's tds to the qh */
+ qh = qh_append_tds (ehci, urb, qtd_list, epnum, &ep->hcpriv);
+ BUG_ON (qh == NULL);
+
+ /* ... update usbfs periodic stats */
+ ehci_to_hcd(ehci)->self.bandwidth_int_reqs++;
+
+done:
+ spin_unlock_irqrestore (&ehci->lock, flags);
+ if (status)
+ qtd_list_free (ehci, urb, qtd_list);
+
+ return status;
+}
+
+/*-------------------------------------------------------------------------*/
+
+/* ehci_iso_stream ops work with both ITD and SITD */
+
+static struct ehci_iso_stream *
+iso_stream_alloc (int mem_flags)
+{
+ struct ehci_iso_stream *stream;
+
+ stream = kmalloc(sizeof *stream, mem_flags);
+ if (likely (stream != NULL)) {
+ memset (stream, 0, sizeof(*stream));
+ INIT_LIST_HEAD(&stream->td_list);
+ INIT_LIST_HEAD(&stream->free_list);
+ stream->next_uframe = -1;
+ stream->refcount = 1;
+ }
+ return stream;
+}
+
+static void
+iso_stream_init (
+ struct ehci_hcd *ehci,
+ struct ehci_iso_stream *stream,
+ struct usb_device *dev,
+ int pipe,
+ unsigned interval
+)
+{
+ static const u8 smask_out [] = { 0x01, 0x03, 0x07, 0x0f, 0x1f, 0x3f };
+
+ u32 buf1;
+ unsigned epnum, maxp;
+ int is_input;
+ long bandwidth;
+
+ /*
+ * this might be a "high bandwidth" highspeed endpoint,
+ * as encoded in the ep descriptor's wMaxPacket field
+ */
+ epnum = usb_pipeendpoint (pipe);
+ is_input = usb_pipein (pipe) ? USB_DIR_IN : 0;
+ maxp = usb_maxpacket(dev, pipe, !is_input);
+ if (is_input) {
+ buf1 = (1 << 11);
+ } else {
+ buf1 = 0;
+ }
+
+ /* knows about ITD vs SITD */
+ if (dev->speed == USB_SPEED_HIGH) {
+ unsigned multi = hb_mult(maxp);
+
+ stream->highspeed = 1;
+
+ maxp = max_packet(maxp);
+ buf1 |= maxp;
+ maxp *= multi;
+
+ stream->buf0 = cpu_to_le32 ((epnum << 8) | dev->devnum);
+ stream->buf1 = cpu_to_le32 (buf1);
+ stream->buf2 = cpu_to_le32 (multi);
+
+ /* usbfs wants to report the average usecs per frame tied up
+ * when transfers on this endpoint are scheduled ...
+ */
+ stream->usecs = HS_USECS_ISO (maxp);
+ bandwidth = stream->usecs * 8;
+ bandwidth /= 1 << (interval - 1);
+
+ } else {
+ u32 addr;
+
+ addr = dev->ttport << 24;
+ if (!ehci_is_TDI(ehci)
+ || (dev->tt->hub !=
+ ehci_to_hcd(ehci)->self.root_hub))
+ addr |= dev->tt->hub->devnum << 16;
+ addr |= epnum << 8;
+ addr |= dev->devnum;
+ stream->usecs = HS_USECS_ISO (maxp);
+ if (is_input) {
+ u32 tmp;
+
+ addr |= 1 << 31;
+ stream->c_usecs = stream->usecs;
+ stream->usecs = HS_USECS_ISO (1);
+ stream->raw_mask = 1;
+
+ /* pessimistic c-mask */
+ tmp = usb_calc_bus_time (USB_SPEED_FULL, 1, 0, maxp)
+ / (125 * 1000);
+ stream->raw_mask |= 3 << (tmp + 9);
+ } else
+ stream->raw_mask = smask_out [maxp / 188];
+ bandwidth = stream->usecs + stream->c_usecs;
+ bandwidth /= 1 << (interval + 2);
+
+ /* stream->splits gets created from raw_mask later */
+ stream->address = cpu_to_le32 (addr);
+ }
+ stream->bandwidth = bandwidth;
+
+ stream->udev = dev;
+
+ stream->bEndpointAddress = is_input | epnum;
+ stream->interval = interval;
+ stream->maxp = maxp;
+}
+
+static void
+iso_stream_put(struct ehci_hcd *ehci, struct ehci_iso_stream *stream)
+{
+ stream->refcount--;
+
+ /* free whenever just a dev->ep reference remains.
+ * not like a QH -- no persistent state (toggle, halt)
+ */
+ if (stream->refcount == 1) {
+ int is_in;
+
+ // BUG_ON (!list_empty(&stream->td_list));
+
+ while (!list_empty (&stream->free_list)) {
+ struct list_head *entry;
+
+ entry = stream->free_list.next;
+ list_del (entry);
+
+ /* knows about ITD vs SITD */
+ if (stream->highspeed) {
+ struct ehci_itd *itd;
+
+ itd = list_entry (entry, struct ehci_itd,
+ itd_list);
+ dma_pool_free (ehci->itd_pool, itd,
+ itd->itd_dma);
+ } else {
+ struct ehci_sitd *sitd;
+
+ sitd = list_entry (entry, struct ehci_sitd,
+ sitd_list);
+ dma_pool_free (ehci->sitd_pool, sitd,
+ sitd->sitd_dma);
+ }
+ }
+
+ is_in = (stream->bEndpointAddress & USB_DIR_IN) ? 0x10 : 0;
+ stream->bEndpointAddress &= 0x0f;
+ stream->ep->hcpriv = NULL;
+
+ if (stream->rescheduled) {
+ ehci_info (ehci, "ep%d%s-iso rescheduled "
+ "%lu times in %lu seconds\n",
+ stream->bEndpointAddress, is_in ? "in" : "out",
+ stream->rescheduled,
+ ((jiffies - stream->start)/HZ)
+ );
+ }
+
+ kfree(stream);
+ }
+}
+
+static inline struct ehci_iso_stream *
+iso_stream_get (struct ehci_iso_stream *stream)
+{
+ if (likely (stream != NULL))
+ stream->refcount++;
+ return stream;
+}
+
+static struct ehci_iso_stream *
+iso_stream_find (struct ehci_hcd *ehci, struct urb *urb)
+{
+ unsigned epnum;
+ struct ehci_iso_stream *stream;
+ struct usb_host_endpoint *ep;
+ unsigned long flags;
+
+ epnum = usb_pipeendpoint (urb->pipe);
+ if (usb_pipein(urb->pipe))
+ ep = urb->dev->ep_in[epnum];
+ else
+ ep = urb->dev->ep_out[epnum];
+
+ spin_lock_irqsave (&ehci->lock, flags);
+ stream = ep->hcpriv;
+
+ if (unlikely (stream == NULL)) {
+ stream = iso_stream_alloc(GFP_ATOMIC);
+ if (likely (stream != NULL)) {
+ /* dev->ep owns the initial refcount */
+ ep->hcpriv = stream;
+ stream->ep = ep;
+ iso_stream_init(ehci, stream, urb->dev, urb->pipe,
+ urb->interval);
+ }
+
+ /* if dev->ep [epnum] is a QH, info1.maxpacket is nonzero */
+ } else if (unlikely (stream->hw_info1 != 0)) {
+ ehci_dbg (ehci, "dev %s ep%d%s, not iso??\n",
+ urb->dev->devpath, epnum,
+ usb_pipein(urb->pipe) ? "in" : "out");
+ stream = NULL;
+ }
+
+ /* caller guarantees an eventual matching iso_stream_put */
+ stream = iso_stream_get (stream);
+
+ spin_unlock_irqrestore (&ehci->lock, flags);
+ return stream;
+}
+
+/*-------------------------------------------------------------------------*/
+
+/* ehci_iso_sched ops can be ITD-only or SITD-only */
+
+static struct ehci_iso_sched *
+iso_sched_alloc (unsigned packets, int mem_flags)
+{
+ struct ehci_iso_sched *iso_sched;
+ int size = sizeof *iso_sched;
+
+ size += packets * sizeof (struct ehci_iso_packet);
+ iso_sched = kmalloc (size, mem_flags);
+ if (likely (iso_sched != NULL)) {
+ memset(iso_sched, 0, size);
+ INIT_LIST_HEAD (&iso_sched->td_list);
+ }
+ return iso_sched;
+}
+
+static inline void
+itd_sched_init (
+ struct ehci_iso_sched *iso_sched,
+ struct ehci_iso_stream *stream,
+ struct urb *urb
+)
+{
+ unsigned i;
+ dma_addr_t dma = urb->transfer_dma;
+
+ /* how many uframes are needed for these transfers */
+ iso_sched->span = urb->number_of_packets * stream->interval;
+
+ /* figure out per-uframe itd fields that we'll need later
+ * when we fit new itds into the schedule.
+ */
+ for (i = 0; i < urb->number_of_packets; i++) {
+ struct ehci_iso_packet *uframe = &iso_sched->packet [i];
+ unsigned length;
+ dma_addr_t buf;
+ u32 trans;
+
+ length = urb->iso_frame_desc [i].length;
+ buf = dma + urb->iso_frame_desc [i].offset;
+
+ trans = EHCI_ISOC_ACTIVE;
+ trans |= buf & 0x0fff;
+ if (unlikely (((i + 1) == urb->number_of_packets))
+ && !(urb->transfer_flags & URB_NO_INTERRUPT))
+ trans |= EHCI_ITD_IOC;
+ trans |= length << 16;
+ uframe->transaction = cpu_to_le32 (trans);
+
+ /* might need to cross a buffer page within a td */
+ uframe->bufp = (buf & ~(u64)0x0fff);
+ buf += length;
+ if (unlikely ((uframe->bufp != (buf & ~(u64)0x0fff))))
+ uframe->cross = 1;
+ }
+}
+
+static void
+iso_sched_free (
+ struct ehci_iso_stream *stream,
+ struct ehci_iso_sched *iso_sched
+)
+{
+ if (!iso_sched)
+ return;
+ // caller must hold ehci->lock!
+ list_splice (&iso_sched->td_list, &stream->free_list);
+ kfree (iso_sched);
+}
+
+static int
+itd_urb_transaction (
+ struct ehci_iso_stream *stream,
+ struct ehci_hcd *ehci,
+ struct urb *urb,
+ int mem_flags
+)
+{
+ struct ehci_itd *itd;
+ dma_addr_t itd_dma;
+ int i;
+ unsigned num_itds;
+ struct ehci_iso_sched *sched;
+ unsigned long flags;
+
+ sched = iso_sched_alloc (urb->number_of_packets, mem_flags);
+ if (unlikely (sched == NULL))
+ return -ENOMEM;
+
+ itd_sched_init (sched, stream, urb);
+
+ if (urb->interval < 8)
+ num_itds = 1 + (sched->span + 7) / 8;
+ else
+ num_itds = urb->number_of_packets;
+
+ /* allocate/init ITDs */
+ spin_lock_irqsave (&ehci->lock, flags);
+ for (i = 0; i < num_itds; i++) {
+
+ /* free_list.next might be cache-hot ... but maybe
+ * the HC caches it too. avoid that issue for now.
+ */
+
+ /* prefer previously-allocated itds */
+ if (likely (!list_empty(&stream->free_list))) {
+ itd = list_entry (stream->free_list.prev,
+ struct ehci_itd, itd_list);
+ list_del (&itd->itd_list);
+ itd_dma = itd->itd_dma;
+ } else
+ itd = NULL;
+
+ if (!itd) {
+ spin_unlock_irqrestore (&ehci->lock, flags);
+ itd = dma_pool_alloc (ehci->itd_pool, mem_flags,
+ &itd_dma);
+ spin_lock_irqsave (&ehci->lock, flags);
+ }
+
+ if (unlikely (NULL == itd)) {
+ iso_sched_free (stream, sched);
+ spin_unlock_irqrestore (&ehci->lock, flags);
+ return -ENOMEM;
+ }
+ memset (itd, 0, sizeof *itd);
+ itd->itd_dma = itd_dma;
+ list_add (&itd->itd_list, &sched->td_list);
+ }
+ spin_unlock_irqrestore (&ehci->lock, flags);
+
+ /* temporarily store schedule info in hcpriv */
+ urb->hcpriv = sched;
+ urb->error_count = 0;
+ return 0;
+}
+
+/*-------------------------------------------------------------------------*/
+
+static inline int
+itd_slot_ok (
+ struct ehci_hcd *ehci,
+ u32 mod,
+ u32 uframe,
+ u8 usecs,
+ u32 period
+)
+{
+ uframe %= period;
+ do {
+ /* can't commit more than 80% periodic == 100 usec */
+ if (periodic_usecs (ehci, uframe >> 3, uframe & 0x7)
+ > (100 - usecs))
+ return 0;
+
+ /* we know urb->interval is 2^N uframes */
+ uframe += period;
+ } while (uframe < mod);
+ return 1;
+}
+
+static inline int
+sitd_slot_ok (
+ struct ehci_hcd *ehci,
+ u32 mod,
+ struct ehci_iso_stream *stream,
+ u32 uframe,
+ struct ehci_iso_sched *sched,
+ u32 period_uframes
+)
+{
+ u32 mask, tmp;
+ u32 frame, uf;
+
+ mask = stream->raw_mask << (uframe & 7);
+
+ /* for IN, don't wrap CSPLIT into the next frame */
+ if (mask & ~0xffff)
+ return 0;
+
+ /* this multi-pass logic is simple, but performance may
+ * suffer when the schedule data isn't cached.
+ */
+
+ /* check bandwidth */
+ uframe %= period_uframes;
+ do {
+ u32 max_used;
+
+ frame = uframe >> 3;
+ uf = uframe & 7;
+
+ /* tt must be idle for start(s), any gap, and csplit.
+ * assume scheduling slop leaves 10+% for control/bulk.
+ */
+ if (!tt_no_collision (ehci, period_uframes << 3,
+ stream->udev, frame, mask))
+ return 0;
+
+ /* check starts (OUT uses more than one) */
+ max_used = 100 - stream->usecs;
+ for (tmp = stream->raw_mask & 0xff; tmp; tmp >>= 1, uf++) {
+ if (periodic_usecs (ehci, frame, uf) > max_used)
+ return 0;
+ }
+
+ /* for IN, check CSPLIT */
+ if (stream->c_usecs) {
+ max_used = 100 - stream->c_usecs;
+ do {
+ tmp = 1 << uf;
+ tmp <<= 8;
+ if ((stream->raw_mask & tmp) == 0)
+ continue;
+ if (periodic_usecs (ehci, frame, uf)
+ > max_used)
+ return 0;
+ } while (++uf < 8);
+ }
+
+ /* we know urb->interval is 2^N uframes */
+ uframe += period_uframes;
+ } while (uframe < mod);
+
+ stream->splits = cpu_to_le32(stream->raw_mask << (uframe & 7));
+ return 1;
+}
+
+/*
+ * This scheduler plans almost as far into the future as it has actual
+ * periodic schedule slots. (Affected by TUNE_FLS, which defaults to
+ * "as small as possible" to be cache-friendlier.) That limits the size
+ * transfers you can stream reliably; avoid more than 64 msec per urb.
+ * Also avoid queue depths of less than ehci's worst irq latency (affected
+ * by the per-urb URB_NO_INTERRUPT hint, the log2_irq_thresh module parameter,
+ * and other factors); or more than about 230 msec total (for portability,
+ * given EHCI_TUNE_FLS and the slop). Or, write a smarter scheduler!
+ */
+
+#define SCHEDULE_SLOP 10 /* frames */
+
+static int
+iso_stream_schedule (
+ struct ehci_hcd *ehci,
+ struct urb *urb,
+ struct ehci_iso_stream *stream
+)
+{
+ u32 now, start, max, period;
+ int status;
+ unsigned mod = ehci->periodic_size << 3;
+ struct ehci_iso_sched *sched = urb->hcpriv;
+
+ if (sched->span > (mod - 8 * SCHEDULE_SLOP)) {
+ ehci_dbg (ehci, "iso request %p too long\n", urb);
+ status = -EFBIG;
+ goto fail;
+ }
+
+ if ((stream->depth + sched->span) > mod) {
+ ehci_dbg (ehci, "request %p would overflow (%d+%d>%d)\n",
+ urb, stream->depth, sched->span, mod);
+ status = -EFBIG;
+ goto fail;
+ }
+
+ now = readl (&ehci->regs->frame_index) % mod;
+
+ /* when's the last uframe this urb could start? */
+ max = now + mod;
+
+ /* typical case: reuse current schedule. stream is still active,
+ * and no gaps from host falling behind (irq delays etc)
+ */
+ if (likely (!list_empty (&stream->td_list))) {
+ start = stream->next_uframe;
+ if (start < now)
+ start += mod;
+ if (likely ((start + sched->span) < max))
+ goto ready;
+ /* else fell behind; someday, try to reschedule */
+ status = -EL2NSYNC;
+ goto fail;
+ }
+
+ /* need to schedule; when's the next (u)frame we could start?
+ * this is bigger than ehci->i_thresh allows; scheduling itself
+ * isn't free, the slop should handle reasonably slow cpus. it
+ * can also help high bandwidth if the dma and irq loads don't
+ * jump until after the queue is primed.
+ */
+ start = SCHEDULE_SLOP * 8 + (now & ~0x07);
+ start %= mod;
+ stream->next_uframe = start;
+
+ /* NOTE: assumes URB_ISO_ASAP, to limit complexity/bugs */
+
+ period = urb->interval;
+ if (!stream->highspeed)
+ period <<= 3;
+
+ /* find a uframe slot with enough bandwidth */
+ for (; start < (stream->next_uframe + period); start++) {
+ int enough_space;
+
+ /* check schedule: enough space? */
+ if (stream->highspeed)
+ enough_space = itd_slot_ok (ehci, mod, start,
+ stream->usecs, period);
+ else {
+ if ((start % 8) >= 6)
+ continue;
+ enough_space = sitd_slot_ok (ehci, mod, stream,
+ start, sched, period);
+ }
+
+ /* schedule it here if there's enough bandwidth */
+ if (enough_space) {
+ stream->next_uframe = start % mod;
+ goto ready;
+ }
+ }
+
+ /* no room in the schedule */
+ ehci_dbg (ehci, "iso %ssched full %p (now %d max %d)\n",
+ list_empty (&stream->td_list) ? "" : "re",
+ urb, now, max);
+ status = -ENOSPC;
+
+fail:
+ iso_sched_free (stream, sched);
+ urb->hcpriv = NULL;
+ return status;
+
+ready:
+ /* report high speed start in uframes; full speed, in frames */
+ urb->start_frame = stream->next_uframe;
+ if (!stream->highspeed)
+ urb->start_frame >>= 3;
+ return 0;
+}
+
+/*-------------------------------------------------------------------------*/
+
+static inline void
+itd_init (struct ehci_iso_stream *stream, struct ehci_itd *itd)
+{
+ int i;
+
+ itd->hw_next = EHCI_LIST_END;
+ itd->hw_bufp [0] = stream->buf0;
+ itd->hw_bufp [1] = stream->buf1;
+ itd->hw_bufp [2] = stream->buf2;
+
+ for (i = 0; i < 8; i++)
+ itd->index[i] = -1;
+
+ /* All other fields are filled when scheduling */
+}
+
+static inline void
+itd_patch (
+ struct ehci_itd *itd,
+ struct ehci_iso_sched *iso_sched,
+ unsigned index,
+ u16 uframe,
+ int first
+)
+{
+ struct ehci_iso_packet *uf = &iso_sched->packet [index];
+ unsigned pg = itd->pg;
+
+ // BUG_ON (pg == 6 && uf->cross);
+
+ uframe &= 0x07;
+ itd->index [uframe] = index;
+
+ itd->hw_transaction [uframe] = uf->transaction;
+ itd->hw_transaction [uframe] |= cpu_to_le32 (pg << 12);
+ itd->hw_bufp [pg] |= cpu_to_le32 (uf->bufp & ~(u32)0);
+ itd->hw_bufp_hi [pg] |= cpu_to_le32 ((u32)(uf->bufp >> 32));
+
+ /* iso_frame_desc[].offset must be strictly increasing */
+ if (unlikely (!first && uf->cross)) {
+ u64 bufp = uf->bufp + 4096;
+ itd->pg = ++pg;
+ itd->hw_bufp [pg] |= cpu_to_le32 (bufp & ~(u32)0);
+ itd->hw_bufp_hi [pg] |= cpu_to_le32 ((u32)(bufp >> 32));
+ }
+}
+
+static inline void
+itd_link (struct ehci_hcd *ehci, unsigned frame, struct ehci_itd *itd)
+{
+ /* always prepend ITD/SITD ... only QH tree is order-sensitive */
+ itd->itd_next = ehci->pshadow [frame];
+ itd->hw_next = ehci->periodic [frame];
+ ehci->pshadow [frame].itd = itd;
+ itd->frame = frame;
+ wmb ();
+ ehci->periodic [frame] = cpu_to_le32 (itd->itd_dma) | Q_TYPE_ITD;
+}
+
+/* fit urb's itds into the selected schedule slot; activate as needed */
+static int
+itd_link_urb (
+ struct ehci_hcd *ehci,
+ struct urb *urb,
+ unsigned mod,
+ struct ehci_iso_stream *stream
+)
+{
+ int packet, first = 1;
+ unsigned next_uframe, uframe, frame;
+ struct ehci_iso_sched *iso_sched = urb->hcpriv;
+ struct ehci_itd *itd;
+
+ next_uframe = stream->next_uframe % mod;
+
+ if (unlikely (list_empty(&stream->td_list))) {
+ ehci_to_hcd(ehci)->self.bandwidth_allocated
+ += stream->bandwidth;
+ ehci_vdbg (ehci,
+ "schedule devp %s ep%d%s-iso period %d start %d.%d\n",
+ urb->dev->devpath, stream->bEndpointAddress & 0x0f,
+ (stream->bEndpointAddress & USB_DIR_IN) ? "in" : "out",
+ urb->interval,
+ next_uframe >> 3, next_uframe & 0x7);
+ stream->start = jiffies;
+ }
+ ehci_to_hcd(ehci)->self.bandwidth_isoc_reqs++;
+
+ /* fill iTDs uframe by uframe */
+ for (packet = 0, itd = NULL; packet < urb->number_of_packets; ) {
+ if (itd == NULL) {
+ /* ASSERT: we have all necessary itds */
+ // BUG_ON (list_empty (&iso_sched->td_list));
+
+ /* ASSERT: no itds for this endpoint in this uframe */
+
+ itd = list_entry (iso_sched->td_list.next,
+ struct ehci_itd, itd_list);
+ list_move_tail (&itd->itd_list, &stream->td_list);
+ itd->stream = iso_stream_get (stream);
+ itd->urb = usb_get_urb (urb);
+ first = 1;
+ itd_init (stream, itd);
+ }
+
+ uframe = next_uframe & 0x07;
+ frame = next_uframe >> 3;
+
+ itd->usecs [uframe] = stream->usecs;
+ itd_patch (itd, iso_sched, packet, uframe, first);
+ first = 0;
+
+ next_uframe += stream->interval;
+ stream->depth += stream->interval;
+ next_uframe %= mod;
+ packet++;
+
+ /* link completed itds into the schedule */
+ if (((next_uframe >> 3) != frame)
+ || packet == urb->number_of_packets) {
+ itd_link (ehci, frame % ehci->periodic_size, itd);
+ itd = NULL;
+ }
+ }
+ stream->next_uframe = next_uframe;
+
+ /* don't need that schedule data any more */
+ iso_sched_free (stream, iso_sched);
+ urb->hcpriv = NULL;
+
+ timer_action (ehci, TIMER_IO_WATCHDOG);
+ if (unlikely (!ehci->periodic_sched++))
+ return enable_periodic (ehci);
+ return 0;
+}
+
+#define ISO_ERRS (EHCI_ISOC_BUF_ERR | EHCI_ISOC_BABBLE | EHCI_ISOC_XACTERR)
+
+static unsigned
+itd_complete (
+ struct ehci_hcd *ehci,
+ struct ehci_itd *itd,
+ struct pt_regs *regs
+) {
+ struct urb *urb = itd->urb;
+ struct usb_iso_packet_descriptor *desc;
+ u32 t;
+ unsigned uframe;
+ int urb_index = -1;
+ struct ehci_iso_stream *stream = itd->stream;
+ struct usb_device *dev;
+
+ /* for each uframe with a packet */
+ for (uframe = 0; uframe < 8; uframe++) {
+ if (likely (itd->index[uframe] == -1))
+ continue;
+ urb_index = itd->index[uframe];
+ desc = &urb->iso_frame_desc [urb_index];
+
+ t = le32_to_cpup (&itd->hw_transaction [uframe]);
+ itd->hw_transaction [uframe] = 0;
+ stream->depth -= stream->interval;
+
+ /* report transfer status */
+ if (unlikely (t & ISO_ERRS)) {
+ urb->error_count++;
+ if (t & EHCI_ISOC_BUF_ERR)
+ desc->status = usb_pipein (urb->pipe)
+ ? -ENOSR /* hc couldn't read */
+ : -ECOMM; /* hc couldn't write */
+ else if (t & EHCI_ISOC_BABBLE)
+ desc->status = -EOVERFLOW;
+ else /* (t & EHCI_ISOC_XACTERR) */
+ desc->status = -EPROTO;
+
+ /* HC need not update length with this error */
+ if (!(t & EHCI_ISOC_BABBLE))
+ desc->actual_length = EHCI_ITD_LENGTH (t);
+ } else if (likely ((t & EHCI_ISOC_ACTIVE) == 0)) {
+ desc->status = 0;
+ desc->actual_length = EHCI_ITD_LENGTH (t);
+ }
+ }
+
+ usb_put_urb (urb);
+ itd->urb = NULL;
+ itd->stream = NULL;
+ list_move (&itd->itd_list, &stream->free_list);
+ iso_stream_put (ehci, stream);
+
+ /* handle completion now? */
+ if (likely ((urb_index + 1) != urb->number_of_packets))
+ return 0;
+
+ /* ASSERT: it's really the last itd for this urb
+ list_for_each_entry (itd, &stream->td_list, itd_list)
+ BUG_ON (itd->urb == urb);
+ */
+
+ /* give urb back to the driver ... can be out-of-order */
+ dev = usb_get_dev (urb->dev);
+ ehci_urb_done (ehci, urb, regs);
+ urb = NULL;
+
+ /* defer stopping schedule; completion can submit */
+ ehci->periodic_sched--;
+ if (unlikely (!ehci->periodic_sched))
+ (void) disable_periodic (ehci);
+ ehci_to_hcd(ehci)->self.bandwidth_isoc_reqs--;
+
+ if (unlikely (list_empty (&stream->td_list))) {
+ ehci_to_hcd(ehci)->self.bandwidth_allocated
+ -= stream->bandwidth;
+ ehci_vdbg (ehci,
+ "deschedule devp %s ep%d%s-iso\n",
+ dev->devpath, stream->bEndpointAddress & 0x0f,
+ (stream->bEndpointAddress & USB_DIR_IN) ? "in" : "out");
+ }
+ iso_stream_put (ehci, stream);
+ usb_put_dev (dev);
+
+ return 1;
+}
+
+/*-------------------------------------------------------------------------*/
+
+static int itd_submit (struct ehci_hcd *ehci, struct urb *urb, int mem_flags)
+{
+ int status = -EINVAL;
+ unsigned long flags;
+ struct ehci_iso_stream *stream;
+
+ /* Get iso_stream head */
+ stream = iso_stream_find (ehci, urb);
+ if (unlikely (stream == NULL)) {
+ ehci_dbg (ehci, "can't get iso stream\n");
+ return -ENOMEM;
+ }
+ if (unlikely (urb->interval != stream->interval)) {
+ ehci_dbg (ehci, "can't change iso interval %d --> %d\n",
+ stream->interval, urb->interval);
+ goto done;
+ }
+
+#ifdef EHCI_URB_TRACE
+ ehci_dbg (ehci,
+ "%s %s urb %p ep%d%s len %d, %d pkts %d uframes [%p]\n",
+ __FUNCTION__, urb->dev->devpath, urb,
+ usb_pipeendpoint (urb->pipe),
+ usb_pipein (urb->pipe) ? "in" : "out",
+ urb->transfer_buffer_length,
+ urb->number_of_packets, urb->interval,
+ stream);
+#endif
+
+ /* allocate ITDs w/o locking anything */
+ status = itd_urb_transaction (stream, ehci, urb, mem_flags);
+ if (unlikely (status < 0)) {
+ ehci_dbg (ehci, "can't init itds\n");
+ goto done;
+ }
+
+ /* schedule ... need to lock */
+ spin_lock_irqsave (&ehci->lock, flags);
+ status = iso_stream_schedule (ehci, urb, stream);
+ if (likely (status == 0))
+ itd_link_urb (ehci, urb, ehci->periodic_size << 3, stream);
+ spin_unlock_irqrestore (&ehci->lock, flags);
+
+done:
+ if (unlikely (status < 0))
+ iso_stream_put (ehci, stream);
+ return status;
+}
+
+#ifdef CONFIG_USB_EHCI_SPLIT_ISO
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * "Split ISO TDs" ... used for USB 1.1 devices going through the
+ * TTs in USB 2.0 hubs. These need microframe scheduling.
+ */
+
+static inline void
+sitd_sched_init (
+ struct ehci_iso_sched *iso_sched,
+ struct ehci_iso_stream *stream,
+ struct urb *urb
+)
+{
+ unsigned i;
+ dma_addr_t dma = urb->transfer_dma;
+
+ /* how many frames are needed for these transfers */
+ iso_sched->span = urb->number_of_packets * stream->interval;
+
+ /* figure out per-frame sitd fields that we'll need later
+ * when we fit new sitds into the schedule.
+ */
+ for (i = 0; i < urb->number_of_packets; i++) {
+ struct ehci_iso_packet *packet = &iso_sched->packet [i];
+ unsigned length;
+ dma_addr_t buf;
+ u32 trans;
+
+ length = urb->iso_frame_desc [i].length & 0x03ff;
+ buf = dma + urb->iso_frame_desc [i].offset;
+
+ trans = SITD_STS_ACTIVE;
+ if (((i + 1) == urb->number_of_packets)
+ && !(urb->transfer_flags & URB_NO_INTERRUPT))
+ trans |= SITD_IOC;
+ trans |= length << 16;
+ packet->transaction = cpu_to_le32 (trans);
+
+ /* might need to cross a buffer page within a td */
+ packet->bufp = buf;
+ packet->buf1 = (buf + length) & ~0x0fff;
+ if (packet->buf1 != (buf & ~(u64)0x0fff))
+ packet->cross = 1;
+
+ /* OUT uses multiple start-splits */
+ if (stream->bEndpointAddress & USB_DIR_IN)
+ continue;
+ length = (length + 187) / 188;
+ if (length > 1) /* BEGIN vs ALL */
+ length |= 1 << 3;
+ packet->buf1 |= length;
+ }
+}
+
+static int
+sitd_urb_transaction (
+ struct ehci_iso_stream *stream,
+ struct ehci_hcd *ehci,
+ struct urb *urb,
+ int mem_flags
+)
+{
+ struct ehci_sitd *sitd;
+ dma_addr_t sitd_dma;
+ int i;
+ struct ehci_iso_sched *iso_sched;
+ unsigned long flags;
+
+ iso_sched = iso_sched_alloc (urb->number_of_packets, mem_flags);
+ if (iso_sched == NULL)
+ return -ENOMEM;
+
+ sitd_sched_init (iso_sched, stream, urb);
+
+ /* allocate/init sITDs */
+ spin_lock_irqsave (&ehci->lock, flags);
+ for (i = 0; i < urb->number_of_packets; i++) {
+
+ /* NOTE: for now, we don't try to handle wraparound cases
+ * for IN (using sitd->hw_backpointer, like a FSTN), which
+ * means we never need two sitds for full speed packets.
+ */
+
+ /* free_list.next might be cache-hot ... but maybe
+ * the HC caches it too. avoid that issue for now.
+ */
+
+ /* prefer previously-allocated sitds */
+ if (!list_empty(&stream->free_list)) {
+ sitd = list_entry (stream->free_list.prev,
+ struct ehci_sitd, sitd_list);
+ list_del (&sitd->sitd_list);
+ sitd_dma = sitd->sitd_dma;
+ } else
+ sitd = NULL;
+
+ if (!sitd) {
+ spin_unlock_irqrestore (&ehci->lock, flags);
+ sitd = dma_pool_alloc (ehci->sitd_pool, mem_flags,
+ &sitd_dma);
+ spin_lock_irqsave (&ehci->lock, flags);
+ }
+
+ if (!sitd) {
+ iso_sched_free (stream, iso_sched);
+ spin_unlock_irqrestore (&ehci->lock, flags);
+ return -ENOMEM;
+ }
+ memset (sitd, 0, sizeof *sitd);
+ sitd->sitd_dma = sitd_dma;
+ list_add (&sitd->sitd_list, &iso_sched->td_list);
+ }
+
+ /* temporarily store schedule info in hcpriv */
+ urb->hcpriv = iso_sched;
+ urb->error_count = 0;
+
+ spin_unlock_irqrestore (&ehci->lock, flags);
+ return 0;
+}
+
+/*-------------------------------------------------------------------------*/
+
+static inline void
+sitd_patch (
+ struct ehci_iso_stream *stream,
+ struct ehci_sitd *sitd,
+ struct ehci_iso_sched *iso_sched,
+ unsigned index
+)
+{
+ struct ehci_iso_packet *uf = &iso_sched->packet [index];
+ u64 bufp = uf->bufp;
+
+ sitd->hw_next = EHCI_LIST_END;
+ sitd->hw_fullspeed_ep = stream->address;
+ sitd->hw_uframe = stream->splits;
+ sitd->hw_results = uf->transaction;
+ sitd->hw_backpointer = EHCI_LIST_END;
+
+ bufp = uf->bufp;
+ sitd->hw_buf [0] = cpu_to_le32 (bufp);
+ sitd->hw_buf_hi [0] = cpu_to_le32 (bufp >> 32);
+
+ sitd->hw_buf [1] = cpu_to_le32 (uf->buf1);
+ if (uf->cross)
+ bufp += 4096;
+ sitd->hw_buf_hi [1] = cpu_to_le32 (bufp >> 32);
+ sitd->index = index;
+}
+
+static inline void
+sitd_link (struct ehci_hcd *ehci, unsigned frame, struct ehci_sitd *sitd)
+{
+ /* note: sitd ordering could matter (CSPLIT then SSPLIT) */
+ sitd->sitd_next = ehci->pshadow [frame];
+ sitd->hw_next = ehci->periodic [frame];
+ ehci->pshadow [frame].sitd = sitd;
+ sitd->frame = frame;
+ wmb ();
+ ehci->periodic [frame] = cpu_to_le32 (sitd->sitd_dma) | Q_TYPE_SITD;
+}
+
+/* fit urb's sitds into the selected schedule slot; activate as needed */
+static int
+sitd_link_urb (
+ struct ehci_hcd *ehci,
+ struct urb *urb,
+ unsigned mod,
+ struct ehci_iso_stream *stream
+)
+{
+ int packet;
+ unsigned next_uframe;
+ struct ehci_iso_sched *sched = urb->hcpriv;
+ struct ehci_sitd *sitd;
+
+ next_uframe = stream->next_uframe;
+
+ if (list_empty(&stream->td_list)) {
+ /* usbfs ignores TT bandwidth */
+ ehci_to_hcd(ehci)->self.bandwidth_allocated
+ += stream->bandwidth;
+ ehci_vdbg (ehci,
+ "sched devp %s ep%d%s-iso [%d] %dms/%04x\n",
+ urb->dev->devpath, stream->bEndpointAddress & 0x0f,
+ (stream->bEndpointAddress & USB_DIR_IN) ? "in" : "out",
+ (next_uframe >> 3) % ehci->periodic_size,
+ stream->interval, le32_to_cpu (stream->splits));
+ stream->start = jiffies;
+ }
+ ehci_to_hcd(ehci)->self.bandwidth_isoc_reqs++;
+
+ /* fill sITDs frame by frame */
+ for (packet = 0, sitd = NULL;
+ packet < urb->number_of_packets;
+ packet++) {
+
+ /* ASSERT: we have all necessary sitds */
+ BUG_ON (list_empty (&sched->td_list));
+
+ /* ASSERT: no itds for this endpoint in this frame */
+
+ sitd = list_entry (sched->td_list.next,
+ struct ehci_sitd, sitd_list);
+ list_move_tail (&sitd->sitd_list, &stream->td_list);
+ sitd->stream = iso_stream_get (stream);
+ sitd->urb = usb_get_urb (urb);
+
+ sitd_patch (stream, sitd, sched, packet);
+ sitd_link (ehci, (next_uframe >> 3) % ehci->periodic_size,
+ sitd);
+
+ next_uframe += stream->interval << 3;
+ stream->depth += stream->interval << 3;
+ }
+ stream->next_uframe = next_uframe % mod;
+
+ /* don't need that schedule data any more */
+ iso_sched_free (stream, sched);
+ urb->hcpriv = NULL;
+
+ timer_action (ehci, TIMER_IO_WATCHDOG);
+ if (!ehci->periodic_sched++)
+ return enable_periodic (ehci);
+ return 0;
+}
+
+/*-------------------------------------------------------------------------*/
+
+#define SITD_ERRS (SITD_STS_ERR | SITD_STS_DBE | SITD_STS_BABBLE \
+ | SITD_STS_XACT | SITD_STS_MMF)
+
+static unsigned
+sitd_complete (
+ struct ehci_hcd *ehci,
+ struct ehci_sitd *sitd,
+ struct pt_regs *regs
+) {
+ struct urb *urb = sitd->urb;
+ struct usb_iso_packet_descriptor *desc;
+ u32 t;
+ int urb_index = -1;
+ struct ehci_iso_stream *stream = sitd->stream;
+ struct usb_device *dev;
+
+ urb_index = sitd->index;
+ desc = &urb->iso_frame_desc [urb_index];
+ t = le32_to_cpup (&sitd->hw_results);
+
+ /* report transfer status */
+ if (t & SITD_ERRS) {
+ urb->error_count++;
+ if (t & SITD_STS_DBE)
+ desc->status = usb_pipein (urb->pipe)
+ ? -ENOSR /* hc couldn't read */
+ : -ECOMM; /* hc couldn't write */
+ else if (t & SITD_STS_BABBLE)
+ desc->status = -EOVERFLOW;
+ else /* XACT, MMF, etc */
+ desc->status = -EPROTO;
+ } else {
+ desc->status = 0;
+ desc->actual_length = desc->length - SITD_LENGTH (t);
+ }
+
+ usb_put_urb (urb);
+ sitd->urb = NULL;
+ sitd->stream = NULL;
+ list_move (&sitd->sitd_list, &stream->free_list);
+ stream->depth -= stream->interval << 3;
+ iso_stream_put (ehci, stream);
+
+ /* handle completion now? */
+ if ((urb_index + 1) != urb->number_of_packets)
+ return 0;
+
+ /* ASSERT: it's really the last sitd for this urb
+ list_for_each_entry (sitd, &stream->td_list, sitd_list)
+ BUG_ON (sitd->urb == urb);
+ */
+
+ /* give urb back to the driver */
+ dev = usb_get_dev (urb->dev);
+ ehci_urb_done (ehci, urb, regs);
+ urb = NULL;
+
+ /* defer stopping schedule; completion can submit */
+ ehci->periodic_sched--;
+ if (!ehci->periodic_sched)
+ (void) disable_periodic (ehci);
+ ehci_to_hcd(ehci)->self.bandwidth_isoc_reqs--;
+
+ if (list_empty (&stream->td_list)) {
+ ehci_to_hcd(ehci)->self.bandwidth_allocated
+ -= stream->bandwidth;
+ ehci_vdbg (ehci,
+ "deschedule devp %s ep%d%s-iso\n",
+ dev->devpath, stream->bEndpointAddress & 0x0f,
+ (stream->bEndpointAddress & USB_DIR_IN) ? "in" : "out");
+ }
+ iso_stream_put (ehci, stream);
+ usb_put_dev (dev);
+
+ return 1;
+}
+
+
+static int sitd_submit (struct ehci_hcd *ehci, struct urb *urb, int mem_flags)
+{
+ int status = -EINVAL;
+ unsigned long flags;
+ struct ehci_iso_stream *stream;
+
+ /* Get iso_stream head */
+ stream = iso_stream_find (ehci, urb);
+ if (stream == NULL) {
+ ehci_dbg (ehci, "can't get iso stream\n");
+ return -ENOMEM;
+ }
+ if (urb->interval != stream->interval) {
+ ehci_dbg (ehci, "can't change iso interval %d --> %d\n",
+ stream->interval, urb->interval);
+ goto done;
+ }
+
+#ifdef EHCI_URB_TRACE
+ ehci_dbg (ehci,
+ "submit %p dev%s ep%d%s-iso len %d\n",
+ urb, urb->dev->devpath,
+ usb_pipeendpoint (urb->pipe),
+ usb_pipein (urb->pipe) ? "in" : "out",
+ urb->transfer_buffer_length);
+#endif
+
+ /* allocate SITDs */
+ status = sitd_urb_transaction (stream, ehci, urb, mem_flags);
+ if (status < 0) {
+ ehci_dbg (ehci, "can't init sitds\n");
+ goto done;
+ }
+
+ /* schedule ... need to lock */
+ spin_lock_irqsave (&ehci->lock, flags);
+ status = iso_stream_schedule (ehci, urb, stream);
+ if (status == 0)
+ sitd_link_urb (ehci, urb, ehci->periodic_size << 3, stream);
+ spin_unlock_irqrestore (&ehci->lock, flags);
+
+done:
+ if (status < 0)
+ iso_stream_put (ehci, stream);
+ return status;
+}
+
+#else
+
+static inline int
+sitd_submit (struct ehci_hcd *ehci, struct urb *urb, int mem_flags)
+{
+ ehci_dbg (ehci, "split iso support is disabled\n");
+ return -ENOSYS;
+}
+
+static inline unsigned
+sitd_complete (
+ struct ehci_hcd *ehci,
+ struct ehci_sitd *sitd,
+ struct pt_regs *regs
+) {
+ ehci_err (ehci, "sitd_complete %p?\n", sitd);
+ return 0;
+}
+
+#endif /* USB_EHCI_SPLIT_ISO */
+
+/*-------------------------------------------------------------------------*/
+
+static void
+scan_periodic (struct ehci_hcd *ehci, struct pt_regs *regs)
+{
+ unsigned frame, clock, now_uframe, mod;
+ unsigned modified;
+
+ mod = ehci->periodic_size << 3;
+
+ /*
+ * When running, scan from last scan point up to "now"
+ * else clean up by scanning everything that's left.
+ * Touches as few pages as possible: cache-friendly.
+ */
+ now_uframe = ehci->next_uframe;
+ if (HC_IS_RUNNING (ehci_to_hcd(ehci)->state))
+ clock = readl (&ehci->regs->frame_index);
+ else
+ clock = now_uframe + mod - 1;
+ clock %= mod;
+
+ for (;;) {
+ union ehci_shadow q, *q_p;
+ __le32 type, *hw_p;
+ unsigned uframes;
+
+ /* don't scan past the live uframe */
+ frame = now_uframe >> 3;
+ if (frame == (clock >> 3))
+ uframes = now_uframe & 0x07;
+ else {
+ /* safe to scan the whole frame at once */
+ now_uframe |= 0x07;
+ uframes = 8;
+ }
+
+restart:
+ /* scan each element in frame's queue for completions */
+ q_p = &ehci->pshadow [frame];
+ hw_p = &ehci->periodic [frame];
+ q.ptr = q_p->ptr;
+ type = Q_NEXT_TYPE (*hw_p);
+ modified = 0;
+
+ while (q.ptr != NULL) {
+ unsigned uf;
+ union ehci_shadow temp;
+ int live;
+
+ live = HC_IS_RUNNING (ehci_to_hcd(ehci)->state);
+ switch (type) {
+ case Q_TYPE_QH:
+ /* handle any completions */
+ temp.qh = qh_get (q.qh);
+ type = Q_NEXT_TYPE (q.qh->hw_next);
+ q = q.qh->qh_next;
+ modified = qh_completions (ehci, temp.qh, regs);
+ if (unlikely (list_empty (&temp.qh->qtd_list)))
+ intr_deschedule (ehci, temp.qh);
+ qh_put (temp.qh);
+ break;
+ case Q_TYPE_FSTN:
+ /* for "save place" FSTNs, look at QH entries
+ * in the previous frame for completions.
+ */
+ if (q.fstn->hw_prev != EHCI_LIST_END) {
+ dbg ("ignoring completions from FSTNs");
+ }
+ type = Q_NEXT_TYPE (q.fstn->hw_next);
+ q = q.fstn->fstn_next;
+ break;
+ case Q_TYPE_ITD:
+ /* skip itds for later in the frame */
+ rmb ();
+ for (uf = live ? uframes : 8; uf < 8; uf++) {
+ if (0 == (q.itd->hw_transaction [uf]
+ & ITD_ACTIVE))
+ continue;
+ q_p = &q.itd->itd_next;
+ hw_p = &q.itd->hw_next;
+ type = Q_NEXT_TYPE (q.itd->hw_next);
+ q = *q_p;
+ break;
+ }
+ if (uf != 8)
+ break;
+
+ /* this one's ready ... HC won't cache the
+ * pointer for much longer, if at all.
+ */
+ *q_p = q.itd->itd_next;
+ *hw_p = q.itd->hw_next;
+ type = Q_NEXT_TYPE (q.itd->hw_next);
+ wmb();
+ modified = itd_complete (ehci, q.itd, regs);
+ q = *q_p;
+ break;
+ case Q_TYPE_SITD:
+ if ((q.sitd->hw_results & SITD_ACTIVE)
+ && live) {
+ q_p = &q.sitd->sitd_next;
+ hw_p = &q.sitd->hw_next;
+ type = Q_NEXT_TYPE (q.sitd->hw_next);
+ q = *q_p;
+ break;
+ }
+ *q_p = q.sitd->sitd_next;
+ *hw_p = q.sitd->hw_next;
+ type = Q_NEXT_TYPE (q.sitd->hw_next);
+ wmb();
+ modified = sitd_complete (ehci, q.sitd, regs);
+ q = *q_p;
+ break;
+ default:
+ dbg ("corrupt type %d frame %d shadow %p",
+ type, frame, q.ptr);
+ // BUG ();
+ q.ptr = NULL;
+ }
+
+ /* assume completion callbacks modify the queue */
+ if (unlikely (modified))
+ goto restart;
+ }
+
+ /* stop when we catch up to the HC */
+
+ // FIXME: this assumes we won't get lapped when
+ // latencies climb; that should be rare, but...
+ // detect it, and just go all the way around.
+ // FLR might help detect this case, so long as latencies
+ // don't exceed periodic_size msec (default 1.024 sec).
+
+ // FIXME: likewise assumes HC doesn't halt mid-scan
+
+ if (now_uframe == clock) {
+ unsigned now;
+
+ if (!HC_IS_RUNNING (ehci_to_hcd(ehci)->state))
+ break;
+ ehci->next_uframe = now_uframe;
+ now = readl (&ehci->regs->frame_index) % mod;
+ if (now_uframe == now)
+ break;
+
+ /* rescan the rest of this frame, then ... */
+ clock = now;
+ } else {
+ now_uframe++;
+ now_uframe %= mod;
+ }
+ }
+}